Apparatus for determining moisture content of tobacco



March 1952 A. w. SCHOENBAUM ETAL' APPARATUS FOR DETERMINING MOISTURECONTENT OF TOBACCO Filed April 20, 1950 9 2 2H 1 "V 1 B I- a v F. m S 1nml B w 9 3 I J. t 4 Q 4/ P 2 I Patented Mar. 4, 1952 UNITED rs-s PATENTorrics APPARATUS FOR DETERMINING MOISTURE CONTENT OF TOBACCO ApplicationApril 20, 1950, Serial N 0. 157,034

2 Claims. 1

This invention relates to a method and apparatus for testing themoisture content of tobacco.

In the handling of tobacco it is frequently necessary to determine themoisture content. Thus in the manufacture of cigarettes, the cut,:blended tobacco is adjusted to proper moisture content before it isdelivered to the cigarette making machines. The tobacco is delivered tothe cigarette making machine in bins or containers mounted on wheels orcasters. It has heretofore been the custom to test the moisture contentof small samples taken from these bins by the "Tag Heppenstall method.In making 'such test, several samples are taken from the differentportions of the bin in a 1 sampling thief and placed in a mixingcontainer. The samples are then mixed, poured into the cylinder of themachine and packed firmly by hand. The cylinder .is then transferred tothe vpress and the press adjusted to maintain a pressure of 150 poundsupon the sample for one minute. The head of the press is provided with apair of electrodes connected in circuit with a galvanometer. Thedeflection of the galvanometer is noted together with the temperature ofthe tobacco and the moisture content then obtained from suitableconversion tables.

In testing the moisture content of uncut tobacco such as strips andtobacco in bulk, thief samples are taken as heretofore described and thesample must then be milled or ground before it is .placed in the Tag:press. Loss of moisture during the grinding operation may thus resultin an incorrect moisture determination.

In the present invention We provide a method of testing in which thetest, when applied to tobacco for cigarette manufacture, is carried outin the bin or container. We employ an electrode connected to thegalvanometer in the same manner as the electrode of the Tag pressconsisting of a. number of prongs mounted on a plate or support offairly large area. This plate or support is carried by the piston rod ofa piston mounted in an air cylinder. The electrode is lowered on to thetobacco and allowed to stand until the tobacco beneath the electrode hasbeen held under the desired pressure for a determined period of time. Areading of the galvanometer deflection and the temperature is thentaken, which is converted to moisture content by the methods heretoforeemployed.

Our proposed method thus eliminates several of the steps heretoforeemployed and also provides more accurate information. By employing .2relatively large electrode prongs extending at least one-half of theheight of the .bin .or container and :by testing the moisture :contentof .a much larger sample of the tobacco in the bin or container, moreaccurate information is obtained.

The test may be similarly applied to tobacco entering cut storage, tostrips in tobacco stemmeries and to tobacco .in bulk.

In the accompanying drawings we have shown, more or :lessdiagrammatically, apparatus suitable for use in practicing the processand forming a part .of the invention. In this showing:

Fig. 1 is-a side elevation showing the electrode device associated withthe air cylinder and showing a tobacco bin in position fora moisturetest;

Fig. 2 is a horizontal, sectional view on line 2-2 .of Fig.1;

Fig. 3 is a "vertical, longitudinal, sectional View of the'prongelectrode; and

Fig. 4 is a transverse, sectional view on line 4-4 ofFig. 2.

Referring to the drawings, the reference numeral I designates a pair ofvertical guides adapted to support :an air cylinder *2 by means ofsuitable transverse "members 3. The air cylinder is connected to asource of air under pressure by a line 4 having :su'itable controlvalves and a pressure gauge (not shown) arranged therein. A piston ismounted in the cylinder and is connected to a piston rod 15 extendingfrom the bottom of the cylinder.

The electrode structure, designated generally bythe reference numeral.6, is secured to the piston rod. It consists of a box-like structurehaving a bottom 1, top 8, side walls 9 and end walls -l-'0 formed of any-'su'1'table material. As shown, it is of relatively large area so thatwhen it is lowered into a bin of tobacco under a predetermined pressurea relatively large sample of tobacco will be maintained at thatpressure.

A board H, to which terminals l2 are connected, is arranged on top ofthe electrode member 6. Within the electrode member, and dependingtherefrom, we provide two rows of electrodes l3. One row of electrodesis connected to one of the terminals l2 and the other row connected tothe other terminal l2 so that when the prongs l3 are lowered into thetobacco and the circuit closed, the circuit is completed from one row ofelectrodes to the other. Each series of electrodes is mounted in anelectrode holder M which may be formed of aluminum or other suitablematerial. Each electrode holder consists of cylindrical sections IE toreceive the electrode prongs, connecting sections l6 and end sectionsI1, the end sections abutting the end walls 10. They may be secured inplace in any suitable maner as by screws 18.

The prongs 13 may be of varying length but are preferably from to 15inches long, depending on the depth of the tobacco in the container.They consist of outer shells 19 having pointed tips 20 pressed into thelower ends of the shells. They are retained in the holders [6 in anysuitable manner, as by means of screws 2|.

In practicing the process, a bin or container 22 in which a supply oftobacco is transported to the tobacco feeder of a cigarette making machine is placed beneath the electrode member 6. These containers aremounted on casters 23 by means of which they may be readily moved aboutthe plant. The electrode member 6 is then lowered on to the surface ofthe tobacco. Being of relatively large area, the mass of tobacco, muchgreater than that heretofore tested in the Ta press, is brought to auniform density, depending upon the air pressure exerted on the pistonin the cylinder. In a specific embodiment of the invention, which hasbeen used with success, the length of the electrode member is 13 /2inches and the width 6 inches. After the pressure has been held on themass of tobacco for a given period of time, such as one minute, areading of the galvanometer deflection in the circuit connected to theterminals i2 is taken. The circuit is not shown because it isconventional. By means of a conversion table this value is convertedinto moisture content value, the electrical conductivity of the tobaccovarying according to the type of tobacco, cut of tobacco, density oftobacco, testing time, moisture content and temperature. By maintainingall of these values constant, with the exception of the moisture contentand the temperature, the moisture content can be determined by thedeflection of the galvanometer. While the conversion is obtained fromthe reading of the galvanometer deflection in the same manner asheretofore obtained, more accurate information results because the massof the tobacco included in the moisture test is much greater than thatobtained by the sampling process. With certain cuts of tobacco it isextremely difficult to obtain a homogeneous sample for proper testing.

Another advantage of the invention is that the constant air pressureapplied to the electrode member is subject to less variation than withthe coil spring type in the regular Tag press.

The life of the electrode prongs is also considerably greater.

In applying the process to tobacco entering cut storage, tobacco strips,or tobacco in bulk, the process is essentially the same. The number ofelectrodes employed, the size of the electrodes and other detailedfeatures of the apparatus may be varied to meet particular requirementsencountered in testing tobacco in various conditions, but the process isessentially as described.

We claim:

1. Apparatus of the character described comprising a pair of verticalguide members, a pair of transverse members connected to the guidemembers, an air cylinder supported by the transverse members, a pistonin the cylinder, a piston rod connected to the piston and projectingfrom the bottom of the cylinder, an electrode member secured to thepiston rod, the electrode member consisting of a box-like structure ofappreciable area having a flat lower surface adapted to engage thesurface of material to be tested, two

series of electrode prongs extending downwardly from the lower surfaceof the electrode member, and an electric terminal connected to each setof electrodes.

2. Apparatus of the character described comprising a pair of verticalguide members, a pair of transverse members connected to the guidemembers, an air cylinder supported by the transverse members, a pistonin the cylinder, 9. piston rod connected to the piston and projectingfrom the bottom of the cylinder, an electrode member secured to thepiston rod, the electrode member consisting of a box-like structure ofappreciable area having a fiat lower surface adapted to engage thesurface of material to be tested, two series of electrode holdersmounted in the electrode member, an electrode mounted in each of saidholders and projecting downwardly from the lower surface of theelectrode member, and an electric terminal connected to each series ofelectrodes.

ALEXANDER W. SCHOENBAUM. JOHN T. ASHWORTH.

REFERENCES CITED The following references are of record in the file ofthis patent:

